The H-II Transfer Vehicle was operated by JAXA, Japan’s national space agency. The spacecraft was Japan’s uncrewed contribution to International Space Station logistics and was also known by its Japanese nickname, Kounotori, meaning “white stork.”
HTV-1 launched on September 10, 2009, beginning a series of nine cargo flights. Each vehicle carried pressurized supplies for the crew and exposed equipment for experiments, including hardware for Japan’s Kibo laboratory. After docking, the station’s Canadarm2 robotic arm captured and berthed the craft; HTVs did not autonomously dock like some other cargo vehicles.
The spacecraft was developed with Mitsubishi Heavy Industries and launched on Japan’s H-IIB rocket. Its large cargo bay was especially valuable after the Space Shuttle’s retirement because it could transport International Standard Payload Racks. The final flight, Kounotori 9, launched in May 2020, and the HTV program was succeeded by HTV-X.